Green Roof Drainage Board

4 NOPHADRAIN PODIUM DECK AND PARKING DECK SYSTEM

Paving, (e.g. concrete pavers ≥80 mm)

Laying course, depth 30-50mm, grit 1-3mm

The inverted roof, a sound construction for roof decks!

ND 600sv Drainage Composite

Thermal insulation e.g. JACKODUR® CFR 500 Standard SF or JACKODUR® CFR 700 Standard SF* 2 layers ND TGF-20 Slip Film Root resistant waterproofing membrane e.g. Hertalan easy cover/easy weld EPDM

*the

choice of insulation material is determined by the

long-term design load (creep) performance

Characteristics of the Nophadrain Podium Deck and Parking Deck System: s Excellent protection of the waterproofing membrane; s Can be combined with an intensive green roof; s Limited build-up; s Stabile sub-base for pavement; s Both pedestrian and trafficked paving (emergency services access); s Proven functionality by means of dynamic load tests (TU-Munich, D).

More information on construction and choice of materials for podium deck and parking deck systems can be found in the Nophadrain brochure entitled “Podium Roof Decks, Parking Roof Decks – design and installation guide”.

Nophadrain BV Mercuriusstraat 10 P.O. Box 3016 NL-6460 HA Kerkrade T +31(0)45 535 50 30 F +31(0)45 535 39 30 E info@nophadrain.nl S www.nophadrain.nl

JACKODUR® KF and JACKODUR® CFR are trademarks of JACKON Insulation GmbH.

GREEN ROOFS PODIUM ROOF DECKS PARKING ROOF DECKS 003.09.08.1000.EN

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N O P HA D RA I N RO O F D E C K S

This information is published by Nophadrain BV as a contribution to good practice in the application of soft and hard landscaped roof decks in the UK. Whilst every care has been taken in its preparation Nophadrain BV excludes any liability for errors, omissions or otherwise arising from the contents of this brochure.

The reader must satisfy themselves as to the principles and practice described in this brochure in relation to any particular application and take appropriate, independent professional advice.

1

INTRODUCTION

2 NOPHADRAIN EXTENSIVE GREEN ROOF SYSTEM

Introduction

Construction build-up

Today, architects and town planners are making practical use of flat roofs and maximising available space by designing contemporary green roofs (for example; to enhance the appearance of a building with “terrace” decks).

The waterproofing membrane, which prevents the ingress of water, should be fully adhered to the roof substrate. Extruded Polystyrene (XPS) boards, the only material suitable for an inverted roof (with a minimum compressive strength of 300kN/m²) is installed. The Nophadrain membrane is placed directly on top of the XPS insulation. The core of this membrane is perforated making it vapour permeable thereby guaranteeing long term insulation performance. A growing medium layer is then applied, the thickness of which is dependent on the desired planting scheme: s extensive: moss, Sedum, herbaceous plants and grasses s intensive: lawn, perennials, shrubs and trees.

Flat roofs may be used to provide planted or landscaped areas which can offer a valuable amenity within the built environment.

Such green roofs can enhance the appearance of the building and provide additional outdoor facilities for building users or enable use for both pedestrian and vehicle traffic.

Lawn, shrubs, bushes, trees Sedum, herbaceous plants, grasses

Building Physics The inverted roof system is well proven, highly durable and ideally suited to the insulation of flat roofs. The inverted roof construction can significantly reduce the risk of condensation in an existing building by keeping the roof structure and the waterproofing layer above the dewpoint temperature.

Although the waterproofing membrane takes the function of the vapour check, attention shall be paid to install a diffusion open layer on the insulation to avoid condensation in the insulation.

ND WSM-50 Water Reservoir Panels

ND 5+1 Drainage Composite

For projects involving hard-landscaping for foot or vehicular traffic, a sub-base should be installed over the Nophadrain membrane, followed by laying a course onto which the flexible paving can be laid.

ND 4+1 Drainage Composite

Thermal insulation e.g. JACKODUR® KF 300 Standard SF or

Determining the thermal efficiency of the inverted roof

JACKODUR® KF 500 Standard SF*

Thermal insulation e.g. JACKODUR® KF 300 Standard SF

The requirement for limiting the heat loss through the building fabric can be satisfied if the U values of the building elements (including thermal bridging) do not exceed the maximum values in the relevant Elemental Methods given in the national Building Regulations: England and Wales: Approved documents L1 & L2, Table 1. Scotland: Technical Standards, Northern Ireland: Technical Booklet F.

2 layers ND TGF-20 Slip Film Root resistant waterproofing membrane e.g. Hertalan easy cover/easy weld EPDM

Root resistant waterproofing membrane e.g. Hertalan easy cover/ easy weld EPDM *the

choice of insulation material is determined by the

long-term design load (creep) performance

The U-value of roofs can be calculated using BS EN ISO 6946 (including the correction for rainwater cooling). For green roofs ignore the effect of soil, vegetation etc.

Advantages of the inverted roof system: Well proven, highly durable form of roof construction; Insulation provides excellent protection of the waterproofing membrane; s Excellent thermal performance – for the lifetime of the structure; s Lightweight; s Significantly reduces the risk of condensation. s s

Characteristics of the Nophadrain Extensive Green Roof System (extensive planting scheme): s Excellent protection of the waterproofing membrane; s Vegetation: moss, Sedum, herbaceous plants and grasses; s Minimal load: from 30kg/m² (including vegetation); s Limited build-up: from 70mm; s Low costs: both in terms of installation and maintenance; s Average annual water retention capacity 50%*; s Run-off coefficient C≥0.5**.

More information on construction and choice of materials for extensive green roof systems can be found in the Nophadrain brochure entitled “Extensive Green Roofs – design and installation manual”.

*average

annual precipitation 650-800mm, depth growing medium

≤100mm **rainfall

intensity of i(15)= 0.03 l/(s.m²), depth growing medium

≤100mm

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ND DGS-I Growing Medium Intensive

ND DGS-E Growing Medium Extensive

The Design When designing a flat roof, attention has to be paid to the choice of roof construction. There are two insulated flat roof systems; a “warm” roof where the waterproof membrane is applied above the insulation and an “inverted” roof. The inverted roof is where the waterproofing membrane is protected from damage by the insulation and is suitably loaded to prevent flotation and wind uplift.

3 NOPHADRAIN INTENSIVE GREEN ROOF SYSTEM

2

Characteristics of the Nophadrain Intensive Green Roof System (intensive planting scheme): s Excellent protection of the waterproofing membrane; s Enhanced choice of plants and layout; s High water retention capacity; s Can be combined with hard-landscaping for foot or vehicular traffic; s High load: from 280kg/m2 (including vegetation/lawn); s Build-up: from 210mm; s High costs (installation and maintenance); s Average annual water retention capacity ≥70%** s Run-off coefficient C≤0.2***

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More information on construction and choice of materials for intensive green roof systems can be found in the Nophadrain brochure entitled “Intensive Green Roofs – design and installation manual”.

**average

annual precipitation 650-800mm , depth growing

medium 250-500mm ***rainfall

intensity of i(15)= 0.03 l/(s.m2), depth growing

medium 250-500mm